package main

import "fmt"

const (
    maxInt = int(^uint(0) >> 1)
    minInt = -maxInt - 1
)

func isMerge(a1, a2 []int) bool {
    min1, max1 := maxInt, minInt
    for _, e1 := range a1 {
        if min1 > e1 {
            min1 = e1
        }
        if max1 < e1 {
            max1 = e1
        }
    }

    for _, e2 := range a2 {
        if e2 == min1-1 || e2 == max1+1 {
            return true
        }
    }

    return false
}

func main() {
    a1 := []int{100, 101}
    a2 := []int{103, 104, 102}
    a3 := []int{103, 104, 105}
    fmt.Println(a1, a2, isMerge(a1, a2))
    fmt.Println(a1, a3, isMerge(a1, a3))

    a4 := []int{222, 221, 220, 219}
    a5 := []int{221, 222, 223, 225, 224}
    fmt.Println(a4, a5, isMerge(a4, a5))
}

[100 101] [103 104 102] true
[100 101] [103 104 105] false
[222 221 220 219] [221 222 223 225 224] true